Hi,
I believe, you using advaned section for sending push from AppHQ. Please use Simple section as message type in the send/schedule push pannel and try to send JSON instead a normal string. You can send as many key-value pair you want in that JSON. The format of the JSON can be as follows:
{"alert”:”Your Message","content-available":"1","customKey":"customValue","badge":"increment","sound":"Default”}
You can achieve your requirement with above JSON. Let me know if you have any further queries.
Regards,
Rajeev